Set variables for AX3 as follows.
ISOFILE=debian-7.5.0-armhf-DVD-1.iso
PATCHLEVEL=2
Set variables for A7 as follows.
ISOFILE=debian-7.5.0-armel-DVD-1.iso
PATCHLEVEL=1
Set variables for A6 as follows.
ISOFILE=debian-7.5.0-armel-DVD-1.iso
PATCHLEVEL=1